This invention relates to measuring devices and more particularly to a gauge to determine the identity of a brake spider and the type of replacement brake shoes to be used.
A conventional brake spider is a bracket affixed at each end of a vehicle axle housing for supporting a brake shoe assembly. Many of these brackets are of the double anchor pin type having a pair of ears with a cylindrical aperture in each ear. A brake shoe has similar apertured ears at one end. A pair of brake shoes are pivotally mounted on the spider with the use of a generally cylindrical anchor pin. The shoes are urged by various arrangements to pivot the shoes on the anchor pins away from and toward the axis of the axle during actuation of the brakes.
Brake spiders of the double anchor pin type are not standarized and require at least two different types of brake shoes that are not interchangeable. Upon removal of the brake shoe, it is very difficult to determine by visual inspection the type of spider and hence the type of replacement brake shoe required.
When relining of brake shoes becomes necessary, one common practice is to replace the entire brake shoe with one having new linings. The average mechanic is faced with the delimma of which type of replacement shoes to be used. An error in choice would not become apparent until the work was completed, and the installation of incorrect shoes might cause brake malfunction or would require additional work to replace the incorrect shoes.